The invention relates to a method of operating a cellular telecommunication system wherein one mobile station communicates with a number of base stations in a macrodiversity mode, and wherein each of the base stations receives a transmission power control signal from the mobile station requesting an increase or a decrease of the transmission power levels. The invention also relates to a corresponding cellular telecommunication system.
In Direct Sequence Code Division Multiple Access (DS-CDMA) cellular telecommunication systems, a mobile station communicates in a so-called macrodiversity mode with a number of base stations. In order to keep the signal qualities of the CDMA signals received by the mobile station from the base stations as constant as possible and at least similar, an inner-loop transmission power control is established. This control creates transmission power control (TPC) signals which are sent from the mobile station to the different base stations. Due to different propagation conditions, e.g. different distances between the base stations and the mobile station, these TPC signals are often received or detected incorrectly by the base stations. This has the consequence that the transmission power levels of the base stations drift apart over the time which is called the random walking problem.